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        <ol class="chapter"><li><a href="../index.html"><strong aria-hidden="true">1.</strong> 超过 88 道练习，任点</a></li><li><a href="../low.html"><strong aria-hidden="true">2.</strong> 易</a></li><li><ol class="section"><li><a href="../hello-world/README.zh.html"><strong aria-hidden="true">2.1.</strong> hello world</a></li><li><a href="../gigasecond/README.zh.html"><strong aria-hidden="true">2.2.</strong> 千兆秒 &gt;&lt; Gigasecond)</a></li><li><a href="../leap/README.zh.html"><strong aria-hidden="true">2.3.</strong> 闰年 &gt;&lt; Leap</a></li><li><a href="../raindrops/README.zh.html"><strong aria-hidden="true">2.4.</strong> 雨滴声 &gt;&lt; Raindrops</a></li><li><a href="../reverse-string/README.zh.html"><strong aria-hidden="true">2.5.</strong> 反转字符串 &gt;&lt; Reverse String</a></li><li><a href="../nth-prime/README.zh.html"><strong aria-hidden="true">2.6.</strong> 第 n 个素数 &gt;&lt; Nth Prime</a></li><li><a href="../bob/README.zh.html"><strong aria-hidden="true">2.7.</strong> 迟钝孩子 &gt;&lt; Bob</a></li><li><a href="../beer-song/README.zh.html"><strong aria-hidden="true">2.8.</strong> 啤酒之歌 &gt;&lt; Beer Song</a></li><li><a href="../proverb/README.zh.html"><strong aria-hidden="true">2.9.</strong> 谚语串烧 &gt;&lt; Proverb</a></li><li><a href="../difference-of-squares/README.zh.html"><strong aria-hidden="true">2.10.</strong> 平方差 &gt;&lt; Difference Of Squares</a></li><li><a href="../sum-of-multiples/README.zh.html"><strong aria-hidden="true">2.11.</strong> 倍数之和 &gt;&lt; Sum Of Multiples</a></li><li><a href="../grains/README.zh.html"><strong aria-hidden="true">2.12.</strong> 谷物 &gt;&lt; Grains</a></li><li><a href="../pythagorean-triplet/README.zh.html"><strong aria-hidden="true">2.13.</strong> 勾股数 &gt;&lt; Pythagorean Triplet</a></li><li><a href="../prime-factors/README.zh.html"><strong aria-hidden="true">2.14.</strong> 素数因子 &gt;&lt; Prime Factors</a></li><li><a href="../series/README.zh.html"><strong aria-hidden="true">2.15.</strong> 子串 &gt;&lt; Series</a></li><li><a href="../armstrong-numbers/README.zh.html"><strong aria-hidden="true">2.16.</strong> 水仙花数 &gt;&lt; Armstrong Numbers</a></li><li><a href="../collatz-conjecture/README.zh.html"><strong aria-hidden="true">2.17.</strong> 3n+1 猜想 &gt;&lt; Collatz Conjecture</a></li><li><a href="../diffie-hellman/README.zh.html"><strong aria-hidden="true">2.18.</strong> 迪菲-赫尔曼密钥交换 &gt;&lt; Diffie Hellman</a></li></ol></li><li><a href="../medium.html"><strong aria-hidden="true">3.</strong> 中等</a></li><li><ol class="section"><li><a href="../saddle-points/README.zh.html"><strong aria-hidden="true">3.1.</strong> 鞍点 &gt;&lt; Saddle Points</a></li><li><a href="../isogram/README.zh.html"><strong aria-hidden="true">3.2.</strong> 等值线 &gt;&lt; Isogram</a></li><li><a href="../say/README.zh.html"><strong aria-hidden="true">3.3.</strong> 英文说数字 &gt;&lt; Say</a></li><li><a href="../run-length-encoding/README.zh.html"><strong aria-hidden="true">3.4.</strong> 游程编码 &gt;&lt; Run Length Encoding</a></li><li><a href="../isbn-verifier/README.zh.html"><strong aria-hidden="true">3.5.</strong> 图书编号 &gt;&lt; ISBN Verifier</a></li><li><a href="../perfect-numbers/README.zh.html"><strong aria-hidden="true">3.6.</strong> 数字也能分类 &gt;&lt; Perfect Numbers</a></li><li><a href="../clock/README.zh.html"><strong aria-hidden="true">3.7.</strong> 时钟 &gt;&lt; Clock</a></li><li><a href="../dot-dsl/README.zh.html"><strong aria-hidden="true">3.8.</strong> DOT DSL</a></li><li><a href="../hamming/README.zh.html"><strong aria-hidden="true">3.9.</strong> 汉明距离 &gt;&lt; Hamming</a></li><li><a href="../simple-linked-list/README.zh.html"><strong aria-hidden="true">3.10.</strong> 简单链表 &gt;&lt; Simple Linked List</a></li><li><a href="../pascals-triangle/README.zh.html"><strong aria-hidden="true">3.11.</strong> 杨辉三角形 &gt;&lt; Pascal's Triangle</a></li><li><a href="../scrabble-score/README.zh.html"><strong aria-hidden="true">3.12.</strong> 字母的分数游戏 &gt;&lt; Scrabble Score</a></li><li><a href="../pangram/README.zh.html"><strong aria-hidden="true">3.13.</strong> 全字母句 &gt;&lt; Pangram</a></li><li><a href="../paasio/README.zh.html"><strong aria-hidden="true">3.14.</strong> PaaS-IO-报告 &gt;&lt; Paasio</a></li><li><a href="../nucleotide-count/README.zh.html"><strong aria-hidden="true">3.15.</strong> 核苷酸计数 &gt;&lt; Nucleotide Count</a></li><li><a href="../luhn/README.zh.html"><strong aria-hidden="true">3.16.</strong> 模 10 算法 &gt;&lt; Luhn</a></li><li><a href="../largest-series-product/README.zh.html"><strong aria-hidden="true">3.17.</strong> 最大数字子串乘积 &gt;&lt; Largest Series Product</a></li><li><a href="../word-count/README.zh.html"><strong aria-hidden="true">3.18.</strong> 单词计数 &gt;&lt; Word Count</a></li><li><a href="../atbash-cipher/README.zh.html"><strong aria-hidden="true">3.19.</strong> Atbash 加密 &gt;&lt; Atbash Cipher</a></li><li><a href="../crypto-square/README.zh.html"><strong aria-hidden="true">3.20.</strong> 密码矩形 &gt;&lt; Crypto Square</a></li><li><a href="../rotational-cipher/README.zh.html"><strong aria-hidden="true">3.21.</strong> 旋转密码 &gt;&lt; Rotational Cipher</a></li><li><a href="../simple-cipher/README.zh.html"><strong aria-hidden="true">3.22.</strong> 简单加密 &gt;&lt; Simple Cipher</a></li><li><a href="../rail-fence-cipher/README.zh.html"><strong aria-hidden="true">3.23.</strong> 栅栏密码 &gt;&lt; Rail Fence Cipher</a></li><li><a href="../etl/README.zh.html"><strong aria-hidden="true">3.24.</strong> ETL</a></li><li><a href="../accumulate/README.zh.html"><strong aria-hidden="true">3.25.</strong> 集合操作 &gt;&lt; Accumulate</a></li><li><a href="../acronym/README.zh.html"><strong aria-hidden="true">3.26.</strong> 术语 &gt;&lt; Acronym</a></li><li><a href="../sieve/README.zh.html"><strong aria-hidden="true">3.27.</strong> 素数筛 &gt;&lt; Sieve</a></li><li><a href="../rna-transcription/README.zh.html"><strong aria-hidden="true">3.28.</strong> RNA 转录 &gt;&lt; RNA Transcription</a></li><li><a href="../triangle/README.zh.html"><strong aria-hidden="true">3.29.</strong> 三角形</a></li><li><a href="../roman-numerals/README.zh.html"><strong aria-hidden="true">3.30.</strong> 罗马数字 &gt;&lt; Roman Numerals</a></li><li><a href="../all-your-base/README.zh.html" class="active"><strong aria-hidden="true">3.31.</strong> 你所的基本</a></li><li><a href="../grade-school/README.zh.html"><strong aria-hidden="true">3.32.</strong> 学册</a></li><li><a href="../binary-search/README.zh.html"><strong aria-hidden="true">3.33.</strong> 二分查找</a></li><li><a href="../robot-simulator/README.zh.html"><strong aria-hidden="true">3.34.</strong> 机器人模拟器</a></li><li><a href="../bracket-push/README.zh.html"><strong aria-hidden="true">3.35.</strong> 括号配套</a></li><li><a href="../luhn-from/README.zh.html"><strong aria-hidden="true">3.36.</strong> Luhn From</a></li><li><a href="../queen-attack/README.zh.html"><strong aria-hidden="true">3.37.</strong> 皇后 攻击</a></li><li><a href="../bowling/README.zh.html"><strong aria-hidden="true">3.38.</strong> 保龄球</a></li><li><a href="../sublist/README.zh.html"><strong aria-hidden="true">3.39.</strong> 子列表</a></li><li><a href="../space-age/README.zh.html"><strong aria-hidden="true">3.40.</strong> 地球年</a></li><li><a href="../luhn-trait/README.zh.html"><strong aria-hidden="true">3.41.</strong> Luhn Trait</a></li><li><a href="../macros/README.zh.html"><strong aria-hidden="true">3.42.</strong> 宏</a></li><li><a href="../allergies/README.zh.html"><strong aria-hidden="true">3.43.</strong> 过敏</a></li><li><a href="../variable-length-quantity/README.zh.html"><strong aria-hidden="true">3.44.</strong> 可变长度数量</a></li><li><a href="../phone-number/README.zh.html"><strong aria-hidden="true">3.45.</strong> 电话号码</a></li><li><a href="../wordy/README.zh.html"><strong aria-hidden="true">3.46.</strong> 罗唆</a></li><li><a href="../tournament/README.zh.html"><strong aria-hidden="true">3.47.</strong> 比赛</a></li><li><a href="../custom-set/README.zh.html"><strong aria-hidden="true">3.48.</strong> 自定义 set</a></li><li><a href="../alphametics/README.zh.html"><strong aria-hidden="true">3.49.</strong> 字母谜题</a></li><li><a href="../two-bucket/README.zh.html"><strong aria-hidden="true">3.50.</strong> 两个桶</a></li><li><a href="../pig-latin/README.zh.html"><strong aria-hidden="true">3.51.</strong> 猪的拉丁文</a></li><li><a href="../diamond/README.zh.html"><strong aria-hidden="true">3.52.</strong> 钻石</a></li><li><a href="../spiral-matrix/README.zh.html"><strong aria-hidden="true">3.53.</strong> 螺旋矩阵</a></li><li><a href="../palindrome-products/README.zh.html"><strong aria-hidden="true">3.54.</strong> 回文产品</a></li><li><a href="../poker/README.zh.html"><strong aria-hidden="true">3.55.</strong> 扑克</a></li><li><a href="../grep/README.zh.html"><strong aria-hidden="true">3.56.</strong> grep</a></li><li><a href="../scale-generator/README.zh.html"><strong aria-hidden="true">3.57.</strong> 音阶生成器</a></li><li><a href="../decimal/README.zh.html"><strong aria-hidden="true">3.58.</strong> 十进制</a></li><li><a href="../anagram/README.zh.html"><strong aria-hidden="true">3.59.</strong> 字谜</a></li><li><a href="../protein-translation/README.zh.html"><strong aria-hidden="true">3.60.</strong> 蛋白质翻译</a></li><li><a href="../robot-name/README.zh.html"><strong aria-hidden="true">3.61.</strong> 机器人名称</a></li><li><a href="../book-store/README.zh.html"><strong aria-hidden="true">3.62.</strong> 书店</a></li></ol></li><li><a href="../high.html"><strong aria-hidden="true">4.</strong> 难</a></li><li><ol class="section"><li><a href="../ocr-numbers/README.zh.html"><strong aria-hidden="true">4.1.</strong> OCR 号码</a></li><li><a href="../minesweeper/README.zh.html"><strong aria-hidden="true">4.2.</strong> 扫雷</a></li><li><a href="../dominoes/README.zh.html"><strong aria-hidden="true">4.3.</strong> 骨牌</a></li><li><a href="../parallel-letter-frequency/README.zh.html"><strong aria-hidden="true">4.4.</strong> 并行字母频率</a></li><li><a href="../rectangles/README.zh.html"><strong aria-hidden="true">4.5.</strong> 矩形</a></li><li><a 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            <div id="content" class="content">
                <main>
                    <a class="header" href="#all-your-base" id="all-your-base"><h1>All Your Base</h1></a>
<a class="header" href="#1-readme" id="1-readme"><h2>1. Readme</h2></a>
<a class="header" href="#你的所有基本" id="你的所有基本"><h1>你的所有基本</h1></a>
<p>将一个数字，表示为一个基数中的数字序列，并转为其他基本</p>
<p>实施通用基本转换。给出一个<strong>a</strong>参数，表示为数字序列，将其转换为基数<strong>b</strong>。</p>
<a class="header" href="#笔记" id="笔记"><h2>笔记</h2></a>
<ul>
<li>尝试自己实现转换。请勿使用其他内容为您执行转换.</li>
</ul>
<a class="header" href="#关于a-hrefhttpsenwikipediaorgwikipositional_notation位置表示法a" id="关于a-hrefhttpsenwikipediaorgwikipositional_notation位置表示法a"><h2>关于<a href="https://en.wikipedia.org/wiki/Positional_notation">位置表示法</a></h2></a>
<p>在位置表示法中，以数字表示<strong>b</strong>可以被理解为权力的线性组合<strong>b</strong>.</p>
<p>数字 42，<em>基本为 10</em>，意思是:</p>
<p><code>(4 * 10^1) + (2 * 10^0)</code></p>
<p>数字 101010，<em>基本为 2</em>，意思是:</p>
<p><code>(1 * 2^5) + (0 * 2^4) + (1 * 2^3) + (0 * 2^2) + (1 * 2^1) + (0 * 2^0)</code></p>
<p>号码 1120，<em>基本为 3</em>，意思是:</p>
<p><code>(1 * 3^3) + (1 * 3^2) + (2 * 3^1) + (0 * 3^0)</code></p>
<p>我想你明白了!</p>
<p><em>是。上面这三个数字完全一样。恭喜!</em></p>
<a class="header" href="#2-开始你的表演" id="2-开始你的表演"><h2>2. 开始你的表演</h2></a>
<pre><pre class="playpen"><code class="language-rust editable">#[derive(Debug, PartialEq)]
pub enum Error {
   InvalidInputBase,
   InvalidOutputBase,
   InvalidDigit(u32),
}

///
/// Convert a number between two bases.
///
/// A number is any slice of digits.
/// A digit is any unsigned integer (e.g. u8, u16, u32, u64, or usize).
/// Bases are specified as unsigned integers.
///
/// Return an `Err(.)` if the conversion is impossible.
/// The tests do not test for specific values inside the `Err(.)`.
///
///
/// You are allowed to change the function signature as long as all test still pass.
///
///
/// Example:
/// Input
///   number: &amp;[4, 2]
///   from_base: 10
///   to_base: 2
/// Result
///   Ok(vec![1, 0, 1, 0, 1, 0])
///
/// The example corresponds to converting the number 42 from decimal
/// which is equivalent to 101010 in binary.
///
///
/// Notes:
///  * The empty slice ( &quot;[]&quot; ) is equal to the number 0.
///  * Never output leading 0 digits. However, your function must be able to
///     process input with leading 0 digits.
///
pub fn convert(number: &amp;[u32], from_base: u32, to_base: u32) -&gt; Result&lt;Vec&lt;u32&gt;, Error&gt; {
   unimplemented!(
       &quot;Convert {:?} from base {} to base {}&quot;,
       number,
       from_base,
       to_base
   )
}

</code></pre></pre>
<a class="header" href="#3-测试代码查看" id="3-测试代码查看"><h2>3. 测试代码查看</h2></a>
<pre><pre class="playpen"><code class="language-rust">
# #![allow(unused_variables)]
#fn main() {
#[test]
fn single_bit_one_to_decimal() {
   let input_base = 2;
   let input_digits = &amp;[1];
   let output_base = 10;
   let output_digits = vec![1];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn binary_to_single_decimal() {
   let input_base = 2;
   let input_digits = &amp;[1, 0, 1];
   let output_base = 10;
   let output_digits = vec![5];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn single_decimal_to_binary() {
   let input_base = 10;
   let input_digits = &amp;[5];
   let output_base = 2;
   let output_digits = vec![1, 0, 1];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn binary_to_multiple_decimal() {
   let input_base = 2;
   let input_digits = &amp;[1, 0, 1, 0, 1, 0];
   let output_base = 10;
   let output_digits = vec![4, 2];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn decimal_to_binary() {
   let input_base = 10;
   let input_digits = &amp;[4, 2];
   let output_base = 2;
   let output_digits = vec![1, 0, 1, 0, 1, 0];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn trinary_to_hexadecimal() {
   let input_base = 3;
   let input_digits = &amp;[1, 1, 2, 0];
   let output_base = 16;
   let output_digits = vec![2, 10];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn hexadecimal_to_trinary() {
   let input_base = 16;
   let input_digits = &amp;[2, 10];
   let output_base = 3;
   let output_digits = vec![1, 1, 2, 0];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn fifteen_bit_integer() {
   let input_base = 97;
   let input_digits = &amp;[3, 46, 60];
   let output_base = 73;
   let output_digits = vec![6, 10, 45];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn empty_list() {
   let input_base = 2;
   let input_digits = &amp;[];
   let output_base = 10;
   let output_digits = vec![];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn single_zero() {
   let input_base = 10;
   let input_digits = &amp;[0];
   let output_base = 2;
   let output_digits = vec![];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn multiple_zeros() {
   let input_base = 10;
   let input_digits = &amp;[0, 0, 0];
   let output_base = 2;
   let output_digits = vec![];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn leading_zeros() {
   let input_base = 7;
   let input_digits = &amp;[0, 6, 0];
   let output_base = 10;
   let output_digits = vec![4, 2];
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Ok(output_digits)
   );
}

#[test]
//#[ignore]
fn invalid_positive_digit() {
   let input_base = 2;
   let input_digits = &amp;[1, 2, 1, 0, 1, 0];
   let output_base = 10;
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Err(Error::InvalidDigit(2))
   );
}

#[test]
//#[ignore]
fn input_base_is_one() {
   let input_base = 1;
   let input_digits = &amp;[];
   let output_base = 10;
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Err(Error::InvalidInputBase)
   );
}

#[test]
//#[ignore]
fn output_base_is_one() {
   let input_base = 2;
   let input_digits = &amp;[1, 0, 1, 0, 1, 0];
   let output_base = 1;
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Err(Error::InvalidOutputBase)
   );
}

#[test]
//#[ignore]
fn input_base_is_zero() {
   let input_base = 0;
   let input_digits = &amp;[];
   let output_base = 10;
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Err(Error::InvalidInputBase)
   );
}

#[test]
//#[ignore]
fn output_base_is_zero() {
   let input_base = 10;
   let input_digits = &amp;[7];
   let output_base = 0;
   assert_eq!(
       convert(input_digits, input_base, output_base),
       Err(Error::InvalidOutputBase)
   );
}

#}</code></pre></pre>
<a class="header" href="#4-答案" id="4-答案"><h2>4. 答案</h2></a>
<p><details></p>
<pre><pre class="playpen"><code class="language-rust">
# #![allow(unused_variables)]
#fn main() {
pub type Digit = u32;

#[derive(Debug, PartialEq)]
pub enum Error {
   InvalidInputBase,
   InvalidOutputBase,
   InvalidDigit(Digit),
}

///
/// Convert a number between two bases.
///
/// A number is any slice of digits.
/// A digit is any unsigned integer (e.g. u8, u16, u32, u64, or usize).
/// Bases are specified as unsigned integers.
///
/// Return an `Err(.)` if the conversion is impossible.
/// The tests do not test for specific values inside the `Err(.)`.
///
///
/// You are allowed to change the function signature as long as all test still pass.
///
///
/// Example:
/// Input
///   number: &amp;[4, 2]
///   from_base: 10
///   to_base: 2
/// Result
///   Ok(vec![1, 0, 1, 0, 1, 0])
///
/// The example corresponds to converting the number 42 from decimal
/// which is equivalent to 101010 in binary.
///
///
/// Notes:
///  * The empty slice ( &quot;[]&quot; ) is equal to the number 0.
///  * Never output leading 0 digits. However, your function must be able to
///     process input with leading 0 digits.
///
pub fn convert&lt;P: AsRef&lt;[Digit]&gt;&gt;(
   digits: P,
   from_base: Digit,
   to_base: Digit,
) -&gt; Result&lt;Vec&lt;Digit&gt;, Error&gt; {
   // check that both bases are in the correct range
   if from_base &lt; 2 {
       return Err(Error::InvalidInputBase);
   }
   if to_base &lt; 2 {
       return Err(Error::InvalidOutputBase);
   }

   // check that all digits are in the correct range specified by the base
   if let Some(&amp;invalid) = digits.as_ref().iter().find(|&amp;num| *num &gt;= from_base) {
       return Err(Error::InvalidDigit(invalid));
   }

   // convert all digits into a single large number
   let mut immediate = digits
       .as_ref()
       .iter()
       .rev()
       .enumerate()
       .map(|(i, &amp;num)| num * from_base.pow(i as u32))
       .fold(0, |accu, num| accu + num);

   // convert number into digits
   let mut res = Vec::new();
   while immediate &gt; 0 {
       res.push(immediate % to_base);
       immediate /= to_base;
   }
   // fix order of digits
   res.reverse();
   Ok(res)
}

#}</code></pre></pre>
<p></details></p>
<hr />
<hr />
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